1. Technical Field
The present invention relates to a sensor unit, a torque detector, and an electric power steering device.
2. Related Art
In order to detect steering torque generated in a shaft of an electric power steering device of a vehicle, a torque detector is used. The torque detector includes a permanent magnet that is fixed to one of an input shaft and an output shaft connected by a torsion bar, a stator that is fixed to the other one of the shafts, and guides a magnetic flux according to a torsion angle between the one shaft and the other shaft, and a sensor unit that converts the magnetic flux guided by the stator into an electric signal, to output the electric signal.
The permanent magnet, and a stator unit are covered with a shaft side housing.
The sensor unit includes a collector that faces the stator, and collectively attracts the magnetic flux guided by the stator, a magnetometric sensor that converts the magnetic flux collectively attracted by the collector into an electric signal, to output the electric signal, and a sensor housing that has a peripheral wall which covers the outside of these collector and magnetometric sensor to hold the collector and the magnetometric sensor therein, and is fixed to the shaft side housing (see, Patent Literature 1 (JP-A-2013-195333)).
The collector is held by the sensor housing so as to form a proper clearance between the collector and the stator when the sensor housing is fixed to the shaft side housing.